Xiaofeng Gong Julian Newman The Role of Deontic Concepts and Commitment in the Policy Specification of Mobile Computing Environment. 807-815 http://springerlink.metapress.com/openurl.asp?genre=article&issn=0302-9743&volume=2889&spage=807 2003 conf/otm/2003 OTM Workshops db/conf/otm/otm2003.html#GongN03